Power source apparatus

Abstract

A power source apparatus includes a transformer having a plurality of paired winding portions of primary and secondary windings wound around cores divided by a gap, a driver, connected to the primary winding of the paired winding portion, for switching energization of the primary winding of the transformer to generate a secondary winding voltage, and a selector for selectively driving one of the plurality of paired winding portions.

We claim: 
     
       1. A lower source apparatus comprising: a transformer having a first and second paired winding portions of primary and secondary windings wound around a plurality of cores, wherein said plurality of cores comprise first, second and third core portions, and said plurality of cores being divided by a gap, and wherein said gap comprises a first gap portion in said first core portion on which said first paired winding portion is wound, a second gap portion in said second core portion on which said second paired winding portion is wound, and a third gap portion in said third core portion, said third gap portion being smaller than said first gap porion and said second gap portion;   driving means, connected to said primary winding of said paired winding portion, for switching energization of said primary winding of said transformer to cause said secondary winding to generate a voltage; and   selecting means for selectively driving one of said plurality of paired winding portions.   
     
     
       2. An apparatus according to claim 1, wherein said first paired winding portion generates a low voltage and a second paired winding portion generates a high voltage. 
     
     
       3. An apparatus according to claim 2, wherein said first paired winding portion generates the low voltage when a power switch is turned on, and said second paired winding portion generates the high voltage in response to a predetermined sequence control signal from said selecting means. 
     
     
       4. An apparatus according to claim 1, wherein said selecting means selects power supply to said primary windings of said paired winding portions. 
     
     
       5. A power source apparatus comprising: a transformer having low and high voltage portions, said low voltage portion having a low voltage generating secondary winding and said high voltage portion having a high voltage generation secondary winding being wound around cores which are divided by a gap;   driving means, connected to a primary winding of said transformer, for switching energization of said primary winding to cause said secondary winding to generate a voltage; and   control means for controlling an output from said high voltage generation secondary winding, said control means being provided with a control winding arranged in said high voltage portion and current control means for controlling a current flowing through said control winding.   
     
     
       6. An apparatus according to claim 5, wherein said transformer includes independent primary windings in said low and high voltage portions. 
     
     
       7. An apparatus according to claim 6, further including selecting means for selecting power supply to one of said primary windings of said low and high voltage portions. 
     
     
       8. An apparatus according to claim 5, wherein said transformer includes a common primary winding in said low and high voltage portions. 
     
     
       9. An apparatus according to claim 5, wherein said current control means comprises detecting means for detecting an output from said high voltage generation secondary winding and comparing means for comparing a reference value with an output from said detecting means, whereby a current of said control winding is controlled in response to an output from said comparing means. 
     
     
       10. An apparatus according to claim 9, wherein said current control means comprises switching means for switching the reference value. 
     
     
       11. An apparatus according to claim 9, wherein said apparatus supplies power source voltages to image forming means, and said switching means switches the reference value in an image formation mode and a mode other than the image formation mode. 
     
     
       12. A power source apparatus comprising: a transformer having a plurality of paired winding portions provided with primary and secondary windings wound around a plurality of cores divided by a gap;   driving means connected to said primary winding of said paired winding portion, for switching energization of said primary winding of said transformer to cause said secondary winding to generate a voltage; and   selecting means for selectively driving one of said plurality of paired winding portions, wherein said secondary windings of said second paired winding portion comprise a high voltage output winding and a high voltage control winding, said high voltage control winding being controlled to control an output from said high voltage output winding.   
     
     
       13. A power source apparatus for supplying electric power to each section of an electrophotographic apparatus, in response to a sequence signal, said power source apparatus comprising: a converter transformer including a primary winding, a first secondary winding and a second secondary winding;   switching means for controlling energization of said primary winding;   first output means for outputting a first voltage according to an output from said first secondary winding during an ON time of said primary winding controlled by said switching means;   selection means responsive to the sequence signal related to an image formation for selecting a level of the first voltage outputted from said first output means; and   second output means for outputting a second voltage according to an output generated on said second secondary winding during an OFF time of said primary winding controlled by said switching means.   
     
     
       14. An apparatus according to claim 13, wherein said converter transformer comprises a third secondary winding for outputting a voltage during both the ON and OFF times of said primary winding. 
     
     
       15. An apparatus according to claims 13 or 14, wherein said first secondary winding generates a low voltage for a load. 
     
     
       16. An apparatus according to claims 13 or 14, wherein said second secondary winding generates a high voltage for a load. 
     
     
       17. A power source apparatus for supplying power to each section of an electrophotographic apparatus including an exposure means, said power source apparatus comprising: a converter transformer including a primary winding, a first secondary winding, a second secondary winding and a third secondary winding;   switching means for controlling energization of said primary winding of said converter transformer;   first output means for causing said first secondary winding to output a voltage during an ON time of said primary winding controlled by said switching means; and   second output means for causing said second secondary winding to output a voltage during an OFF time of said primary winding controlled by said switching means, wherein said third secondary winding outputs a voltage to the exposure means during both the ON and OFF times of said primary winding.   
     
     
       18. An apparatus according to claim 13, wherein an AC load is connected between said third secondary winding and said exposure means. 
     
     
       19. An apparatus according to claim 18, wherein said AC load comprises an inductance. 
     
     
       20. A power source apparatus comprising: a transformer having first and second paired winding portions of primary and secondary windings wound around a plurality of cores, wherein said plurality of cores comprise first and second core portions, and said plurality of cores being divided by a gap, said gap having a first gap portion in said first core portion on which the first paired winding portion is provided, and a second gap portion in said second core portion on which the second paired winding portion is provided, said second gap portion being larger than said first gap portion; and   driving means connected to said primary winding of said paired winding portion, for switching energization of said primary winding of said transformer to cause said secondary winding to generate a voltage, wherein said first paired winding portion generates a low voltage and said second paired winding portion generates a high voltage.   
     
     
       21. An apparatus according to claim 20, further comprising selecting means for selectively driving said second pair winding portion. 
     
     
       22. A power source apparatus for supplying electric power to each section of an electrophotographic apparatus, said power source apparatus comprising: a converter transformer including a primary winding, a first secondary winding, a second secondary winding and a third secondary winding;   switching means for controlling energization of said primary winding of said converter transformer;   first output means for generating low voltage DC output in accordance with an output generated on said first secondary winding, during an ON time of said primary winding controlled by said switching means;   second output means for generating high voltage DC output in accordance with an output generated on said second secondary winding, during an OFF time of said primary winding controlled by said switching means; and   third output means for generating AC output, in accordance with an output generated on said third secondary winding, during the ON and OFF times of said primary winding controlled by said switching means.   
     
     
       23. An apparatus according to claim 22, wherein said first output means is adapted to supply electric power to a control section for sequence control of said electrophotographic apparatus. 
     
     
       24. An apparatus according to claim 22, wherein said second output means is adapted to supply electric power to charging means of said electrophotographic apparatus. 
     
     
       25. An apparatus according to claim 22, wherein said third output means is adapted to supply electric power to exposure means of said electrophotographic apparatus.